The present invention relates generally to wireless communications, and more particularly, to long term evolution LTE and long term evolution advanced LTE-A uplink UL power control.
In LTE and LTE-Advanced systems, uplink power control is crucial to reduce the interference and improve system throughput. 3GPP has defined fractional power control (FPC) to control the uplink transmission power. The major issue is that the interference created at neighboring cells highly depends on the users scheduled in the present cell. As a result, signal-to-interference-noise-ration SINR estimation, user scheduling, and modulation and coding scheme MCS selection become challenging in neighboring cells.
There has been a proposal to compensate the transmit power by a fraction of the difference between the pathloss to the serving cell and that to the second strongest cell. Another technique proposed to continuously adjust the transmission power to maintain a target total interference power a user creates to the entire system. However, the individual interference a user creates to a given neighboring cell may still be highly variable and heavily dependent on the user that is scheduled in the present cell.
Accordingly, there is a need for improved LTE and LTE-A uplink power control.